QUIET BUT POWERFUL

Drilling and foundation machines are getting bigger and faster. But, as Mitchell Keller reports, despite their size and speed, today’s equipment is smarter and quieter than ever

The Epiroc SmartROC T30 R, which includes the company’s automating RCS (rig control system)

IMAGE: EPIROC

A Liebherr LRH 100 pilling rig with noise reduction capabilities works on a construction site

IMAGE: LIEBHERR

It’s summer in the city; barriers and fencing block access and the view to a city block where foundation and drilling work is underway. On the streets, air brakes from public buses hiss and squeal while traffic honks and rolls along the boulevards. But, from the construction site, not a peep.

In this situation, the construction site is quiet as a mouse but not from inactivity. No, as the workers run giant drills to prepare the site’s foundation, the low emission of noise and vibration is the culmination of decades of design and technology improvement that have made this sector smarter, quieter, and safer than ever before.

“Today, this industry is much more modern,” Stefan Mewes of Liebherr Group tells International Construction. Mewes has spent 30 years in the more than century-old segment, wherein drilling and piling has gone from freefall hammers, to steam, to diesel, and through today’s hydraulic hammers.

Mewes acknowledges that, despite those advancements, little has changed optically. Using pile driving as an example, Mewes says, “These hammers are impacting the piles into the ground. You’re compressing the pile, and then there’s a wave running down the pile and, at the end, the pile standing on a bearing layer to bring the load from the building or bridge.”

The same as it ever was, he says. But the gains these days are in the minute details and data. Hydraulic drills and drivers, Mewes says, have become hyper energy-resourceful; he estimates efficiency on those machines rates near 95%, more than 30% higher than combustion-based machines, by his estimates.

The main reason for increased efficiency – like all hydraulic tooling – is the closed-loop system where pressure and flow of the hydraulic fluid is continuously regulated.

In a segment like foundations, the steady power output hydraulic drills provide means the machine can more easily adapt to changing loads and compaction. It also releases operators from having to control piling manually. The electric revolution has also aided remote operations, something Mewes says Liebherr calls ‘unplugged’ work.

“It is a proven design with proven components, and we are certain that these meet and fulfil the tough requirements on the jobsite. The piling machine can be operated without a cable, therefore battery-powered and ‘unplugged,’” he says.

There are no limitations in terms of machine performance and application, compared to the conventional version with diesel engine/ combustion engine.”

With more productivity and less intensive operation, engineers have seemingly focused on increasing capabilities, whether that’s drilling to new depths, implementing new tech, or increase stabilisation.

A Bauer eBG 36 drills through a rocky soil surface

IMAGES: BAUER GROUP

For example, Bauer’s SPEX 4 configuration for its BG 23 H piling machine – powered by either a 186kW or 225kW Caterpillar electric engines – drilled to new depths using a continuous flight auger (CFA) method.

Tobias Rager, Bauer Maschinen managing director (chief operations and chief technology officer), says, “With this special single-pass extreme configuration, it is possible to achieve a method with a compact drilling rig with an operating weight of only 79 tonnes.”

Rager adds that a rope arrangement with the SPEX 4 increases retraction force by drilling depth of up to 27m using the CFA 30%.

Bauer COO and CTO Tobias Rager

Embracing new tech

Construction technology is a huge reason behind some of the progress in foundation work efficacy.

The most advanced developments have come within automation, telematics, and remote control. For instance, Bauer subsidiary RTG Rammtechnik released Operation Remote Control, which the company said is a ‘world first’ in the field of telescopic leaders.

Bernhard Lindermair, Bauer Maschinen’s head of product lines, says, “Using this tool, which is available for all RTG equipment, the operator can control all functions externally – from set-up and drilling to impact driving.

“As a result, the entire set-up process can be carried out by a single person in about 15 minutes. This makes one-man operation possible, resulting in considerable safety improvements, particularly on cramped construction sites.”

Speed was also key to Swedenbased Epiroc’s SmartROC T30 R surface radio remote drill rig, which was officially released in April. It was built with the promise of offering contractors more metres per shift with its ‘smart’ system.

Herrenknecht’s Offshore Foundation Drilling (OFD) technology is lowered into the sea

IMAGE: HERRENKNECKT

SECOND WIND FARM WITH HERRENKNECHT OFD TECHNOLOGY

Starting in May, German-based Herrenknecht – a manufacturer of tunnel boring machines – said its Offshore Foundation Drilling (OFD) technology has been used in the construction of the Noirmoutier wind farm off the French Atlantic coast.

For the new wind farm, OFD is drilling boreholes for 61 monopiles in the rocky Atlantic Ocean seabed – at depths up to 36m – between the islands of Noirmoutier and Yeu. Each monopile has a diameter of 7m and will serve as the foundation for one of the more than 200m-high wind turbines.

DEME Group of Belgium – a dredging and marine engineering firm – is driving in the monopiles for the Noirmoutier wind farm. DEME and Herrenknecht jointly developed the drilling and installation method. Herrenknecht supplies the drilling technology and provides specialized drilling personnel who are constantly on board the installation vessel in shifts during the project.

The drilling for Noirmoutier will be carried out with the 350-tonne OFD machine, which has a drilling diameter of 7,700mm.

The T30 R is built on the same platform as Epiroc’s SmartROC T25 R; the company’s flagship construction and quarrying drill rig, which was released in May 2023.

The new unit uses Epiroc’s Rig Control System (RCS), which the company said, “enables the highest technology and automation level within the segment.”

NEW GENERATION OF CORE DRILL MOTORS

While the biggest of machines might take up the most attention (and certainly the most space) in the drilling sector, the handheld and portable segment continues innovating, as well.

Austria-based abrasives, sawing, and drilling equipment manufacturer Tyrolit released a new range of air-cooled electric drill motors (the DME20, DME26, and DME32), which come in 2-, 2.6or 3.2-kW versions.

The company said the new suite was designed to be user-friendly and reliable. “The air-cooled drill motors have an extremely robust full metal housing, a three-speed gearbox with oil bath, as well as mechanic and electric overload protection,” says Tyrolit. “They also come with a levelling aid and a practical service and performance indicator.”

The DME20 can be used for wet or dry drilling as either a hand-held or rig-based model.

The DME26 and DME32 come with either a quick clamping system or a universal plate, depending on the application needs.

A worker uses a Tyrolit DME32 drill motor on a concrete wall

IMAGE: TYROLIT FACEBOOK

The RCS hardware and software is the main technology facilitating both Epiroc’s drill rigs’ onboard automation solutions. “An automated rod handling system allows to add drill rods manually or automatically to reach the desired hole depth,” explained Epiroc. “This solution supports sustainable and consistent operations and increases average productivity.”

The RCS also enables access to the Epirocdeveloped Hole Navigation System (HNS). Utilising modern software that connects with satellites on terra-based base stations, the HNS uses multiple points of data to ensure machines are drilling to the correct depth at the right angle.

“HNS provides an exact placement of holes, hole angles, and depths. This delivers better blast results, better fragmentation, and improved load-ability with fewer explosives,” confirmed Epiroc. “A more uniform drill pattern will result in a higher quality blast result that will deliver better fragmentation and minimises the need for secondary breaking. Good fragmentation can increase crusher throughput by up to 30%.”

Marcus Leü, global product manager at Epiroc, added, “The combination of great terrainability, large coverage area, and the powerful COP SC19HF [rock drill], makes the rig outstanding and suitable to manage even the most challenging projects.”

Turning down the noise

Even though hyper-precision via new technology and automation may seem like the biggest advancements for any constructionsector machinery, drilling and foundation companies seem most eager to discuss their noise and vibration reduction in recent years. Back to that quiet scene at the start of this feature – is this the construction site of the future: one without booming sound and disruptive tremors? Liebherr’s Mewes says changing how the company measured sound led to further reducing its impact both on-site and beyond. “You can measure the sound pressure. It’s measuring the fluctuations in the air,” he explains, but notes a better calculation is of the sound power. “It’s independent from the surrounding area. It’s a number where you can really compare different machines.”

Sound power is the total airborne sound energy radiated by a sound source per unit of time. Simply put, sound power is a cause and sound pressure the effect.

“This makes sound power levels ideal for product labelling, for specifying noise emission limits for devices, and for verifying compliance with limits,” says Mewes, noting his company has used this direction to explore noise-reduction innovations.

The industry has multiple tools to reduce noise, from rubber and spring mounting systems that isolate and absorb vibration to feedback systems that measure noise during operations and precision/symmetrical engineering and design that limits sound pollution from imbalanced operation.

Drilling and boring works run alongside coal mining operations

IMAGE: ADOBE STOCK

TWO TBMS LAUNCHED FOR ‘WORLD’S LONGEST’ SUBSEA TUNNEL FOR HIGH-SPEED RAIL

In May, two super-large diameter slurry tunnel boring machines (TBM), developed by China Railway Construction Heavy Industry Corporation Limited (CRCHI), were launched from opposite directions in Ningbo and Zhoushan for the Jintang subsea tunnel of the newly constructed Ningbo-Zhoushan Railway.

The system supports trains travelling as fast as 250km an hour and spans 77km. The simultaneous rotation of the cutterheads of the two TBMs marks the start of the TBM advance phase for the world’s longest subsea high-speed railway tunnel.

With a total length of 135m and a maximum excavation diameter of 14.57m, the TBMs will create a tunnel that stretches from Yinzhou District in Ningbo City in the west to Jintang Town in Zhoushan City in the east, spanning a total length more than 16km. The TBM section runs just more than 11km long, with a maximum buried depth of 78m.

The tunnel crosses under the 100,000 tonne Jintang main navigation channel, which marks the ‘world’s first’ case of subsea docking and disassembly of super-large diameter shield machines, the state-owned company said.

The varying geological conditions of the work is precisely why these TBMs go through rigorous testing. “China is very big and different areas means different ground conditions,” says a CRCHI representative. “Some is hot, some soft, some rich in water, some have to cross a river or lake. Geology is so various that we have to design different configuration of the cutters.”

The representative added that CRCHI’s TBMs are all customised and go through multiple testing and approval processes before being delivered to the jobsite. “First we have the factory acceptance test. That’s after we put everything together, we invite our customer to go to our factory to test each and every other system one by one.”

After this the machine is dismantled and then transported to the jobsite where it is put back together and a site acceptance test (SAT) takes place before it is ready to bore (RTB).

CRCHI added that they are developing autonomous systems for TBMs. “Our target timeframe is that within several years, we can reduce the total working staff from 20-30 people down to several people staying in the tunnel. And in the future, we don’t want to keep any people within the tunnel. It’s our vision.”

A CRCHI tunnel boring machine prior to its launch to create the ‘world’s longest’ subsea tunnel

IMAGE: CRCHI

“Ground pressure visualisation we call it,” says Mewes of a telematic feature on Liebherr machines. While safety is paramount in keeping a unit on its tracks or wheels, Mewes notes it also reduces sound.

For those wondering why sound above all is of specific focus in the sector: look no further than today’s labour market where the sector is struggling to find workers.

Quieter machines that vibrate less (reducing the effect on the body) are easier to work with and, coupled with automated controls, make for a more rewarding workday.

Cities may still resonate from the hustle-andbustle of human’s going about their day, but don’t blame the drilling and foundation works at the construction site across the block: they’re just quietly doing their job.